Cooling Tower

How to reduce the COD in sewage treated water?

We are planning to use the sewage treated water for our plant cooling tower makeup. TDS and COD are the parameters on the higher side viz 1000 mg/l and 48 mg/lunits respectively.is there any cost effective treatment available to reduce the COD and TDS/ otherwise are these parameters are OK for usage. Other parameters like silica, Hardness, turbidity, BOD, PH are within the limits.pl suggest.

BOD & COD and Oil & Grease parameters are high in treated water. How to reduce these idk.